fat_headfandomcom-20200215-history
Health Benefits of a Low Carb, High Fat Diet
This is a document that I put together as an outline of my research. Unfortunately, I started capturing actual references late, so I don't have papers for everything. Some of these are also going from memory, so they might not all be 100% accurate, but I provide this as a starting point for benefits of a low carb, high fat diet. All of the points I make below are backed up by scientific research (to the best of my memory; I started taking notes late :). These are not Dr. Quack's ideas, but rather the results of rigorous, scientific research in fields such as endocrinology, neurology, cardiology, and diabetes. It says much about the state of "science" (or lack thereof) in nutrition and obesity and the influence of politics on nutrition that this well known, well published science has not impacted the dogma surrounding low-fat, high-carb diets. Some of these reactions are simplified. The start and endpoints are correct, but I haven't listed every step, in the interest of not writing a book. If the research is preliminary, I try to identify that. =Definitions= * Carbohydrate: In context of this document, a carbohydrate is a non-fiber mono- or poly-saccharine. It is something your body can digest and burn. * Carb: This is a short-cut for simple-carbohydrate-rich foods. * Fiber: Macro-nutrients that your body is not able to digest. These come in two types: soluble and non-soluble. * Low-carb Diet: A diet of less than 60-80g of carbohydrates per day (depends on the person). * Diabetes in this context is Type II Diabetes (what used to be called "Adult Onset", before kids started getting it). * Metabolic Syndrome: A combination of heart disease, high cholesterol, high blood pressure, insulin resistance, diabetes, gout, and other symptoms that tend to cluster together. * Fructose: A type of carbohydrate found in fruit, corn, and table sugar. It is combined with glucose to create High Fructose Corn Syrup (HFCS), which is almost identical to table sugar and processed identically by the body. Table sugar and HFCS are both about 1/2 fructose. =The Downsides to Sugars= Sugars get put into two categories: those processed as glucose (which includes lactose) and those processed as fructose. Glucose-related sugars aren't particularly good for you; but fructose can be downright dangerous. * Glucose increases the production of insulin. While this is obvious and well known, it will be important when we look at what that insulin does later. * Metabolically, fructose is processed in the liver exactly the same way that alcohol is. This means regular consumption causes all the same chronic liver and metabolic problems that chronic alcoholism causes. Fructose is alcohol without the buzz. This is particularly problematic because HFCS and sugar are added to pretty much everything. * The metabolic pathway through the liver of fructose uses extra phosphate, which leads to a buildup of uric acid. Uric acid causes high blood pressure. * Glucose competes with Vitamin C for absorption in the body. Vitamin C is required for white blood cells to do their jobs of fighting infections. Removing dietary glucose means the dietary Vitamin C can be absorbed and utilized much more easily. * Tooth and gum disease has been shown to be significantly correlated with other, chronic diseases (likely due to the long-standing infection and inflammation it causes). While everybody knows sugar causes cavities, what isn't as well known is that low-carb diets high in calcium, vitamin D, and phosphorous actually causes new layers of dentin (the layer under the enamel) to be laid down on the tooth, effectively healing the tooth. * Excess sugar is taken out of the blood by the liver. It does this by turning it into saturated fat. Saturated fats also increase insulin resistance. * Consistent, high blood sugar leads to glycosylation, which is the inappropriate binding of proteins to sugar. Glycosylated proteins oxidize much faster (which is bad and why anti-oxidants are good). These oxidized proteins include extorted LDL (e.g. that "bad" cholesterol), which increases inflammation of the arteries, increasing the risk and damage of heart disease. * Studying multiple countries, every 150 total calories a person takes in has barely any effect on diabetes. But if those 150 calories were from sugar, it increased the prevalence of diabetes seven-fold. * Sugar activates the same neural pathways as drugs like nicotine and cocaine. This leads to the same kind of reward-seeking addictive cycle. * There is evidence that low carb, high fat diets may decrease the likelihood of dementia and Alzheimer's disease. This is still rudimentary. * There is also evidence that low carb diets may slow cancer or reduce the chances of benign tumors turning malignant. This is still rudimentary. * Finally, there is beginning to be a trickle of evidence that autoimmune diseases, like MS, allergies, IBS, and possibly even Type I diabetes, have some relationship with the diet of highly processed, highly carb-laden food. Significant problems with fructose only occur when taking in large quantities without fiber, which includes all sugary drinks (soda, energy drinks and fruit juice) and most processed foods, since the foods are stripped of fibers to keep them from spoiling. Similar to people drinking an alcoholic beverage or two a day without suffering ill effects, eating an apple and some berries every day can provide much value. =The Benefits of Ketosis= Ketosis is the result of lowering carbohydrates to less than 30-50g per day. This moves your body into a state where it manufactures its own glucose-like fuel called ketones. This is the diet I am following. * Ketosis takes significant energy to produce ketones out of fatty acids. This energy is part of the so-called "metabolic advantage" of ketosis. * Studies are showing that the muscles have better aerobic performance when utilizing ketones. While these are preliminary, they are showing better muscle performance for less oxygen than when using glucose. One study showed total energy expenditure on low-carb diets was 200-400 calories per day more than on low-fat diets.Effects of Dietary Composition on Energy Expenditure During Weight-Loss Maintenance * In order to produce ketones, the body needs to break triglycerides down. This has the benefit of cleaning up the blood and reducing the likelihood of heart disease. It is also where much of the serum glucose that remains in the body on a carbohydrate-free diet comes from. * A Harvard study showed that people eating a ketogenic diet burned more calories per day than those eating a low-fat diet. The body's physiology is such that the food you eat controls your output (and thus physical activity), so increasing calories burned leads to more exercise (which is backwards of what is traditionally taught). =The Well Regulated Hormones= Hormones drive all the energy storage and usage reactions in the body (amongst other things). The body wants to be in homeostasis (e.g. it wants to stay the same). Weight gain and loss can only occur through changes to the hormones that control those systems. Insulin Insulin is the primary energy-regulatory hormone. While there are multiple hormones that cause energy to be used, insulin overrides them all and causes energy to be stored. Too much insulin in the blood leads to insulin resistance, where the pancreas must produce more insulin for the same effect. This leads to a vicious circle and, eventually, diabetes. * Ingesting glucose increases insulin. Insulin increases fat storage and, when muscles are constantly subjected to it, causes muscles to decrease their sensitivity to it. This requires more insulin to be used to cause the muscles to accept the glucose and can eventually lead to diabetes. * A low-carb diet lowers insulin levels and reduces variability in insulin levels throughout the day. While a low-carb diet lowers insulin, there is still insulin being produced and in the bloodstream. * Insulin increases fat storage by "turning on" an enzyme called lipoprotein lipase. Lipoprotein lipase is an enzyme that allows fatty acid into cells. It breaks the fatty acids off of triglycerides. Without it, fat won't be stored. * To keep blood sugar in check, the pancreas will dump a lot of stored insulin when it detects carbohydrates. This dumping causes blood sugar to drop, which turns on cravings to get the blood sugar stabilized. * Without insulin, the liver will produce a stable amount of glucose for the body using gluconeogenesis. Insulin turns off gluconeogenesis, which allows blood sugar levels to bounce up and down. * Fat stored due to insulin tends to be visceral (abdominal) fat. This is the "killer" fat that causes organ failure. * Prolonged insulin exposure interferes with growth hormone activation on the cell. Occasional exposure enhances growth hormone activation. You need the growth hormone activation because, without it, you cannot get a full protein into the cell. * Insulin decreases fat lipolysis, which is the conversion of lipids into energy. It is very difficult to burn fat when insulin levels are high. Instead of burning fat, your body will burn everything else that can turn to sugar, which means muscle. * Insulin directs the generation of new fat cells (where is puts the excess blood sugar). This requires generating cholesterol, which is necessary for cell walls. As a result, lowering insulin lowers serum cholesterol. * Reducing insulin increases DHEA. DHEA is a hormone produced by the adrenals that reduces osteoporosis and may reduce symptoms of depression. * Insulin increases fluid retention; it increases the excretion of magnesium and potassium; and it increases sympathetic tone. It also increases smooth muscle cell proliferation and enhances endothelial cell production. Taken together, these lead to high blood pressure. * Insulin results in increased production of small, dense LDL (VLDL or the "really bad" cholesterol) as well as causes lipid-containing lesions and thickening of arterial walls. This is the definition of heart disease. * Insulin clears dopamine from receptors in the brain. Combined with the cravings due to low blood sugar, there is a powerful physiological and psychological drive to eat carby foods. Leptin Leptin is one of the satiety hormones. * Leptin is produced by fat cells as they absorb fatty acids. The signal is received by the hypothalamus, and signals the body to stop eating. * Insulin, which is dumped on a high-carb meal, blocks the reception of leptin in the hypothalamus, so you don't get satiated. * Worse, when leptin is regularly blocked, the brain thinks it's in "starvation" mode and ratchets up fat storage, decreases metabolic rate (and therefore your desire to perform any activity), and increases hunger. * Since insulin blocks the reception of leptin, the body must produce more leptin. This leads to leptin resistance, which means you never feel satiated. Again, another vicious cycle. Ghrelin Ghrelin is excreted by the stomach. It tells your brain that your stomach is empty. Thank ghrelin for your rumbling stomach. Reducing ghrelin is one step towards satiety. * Due to differences in metabolic pathways, fructose will not affect ghrelin production. Your stomach will literally never tell you that you are full while eating foods that are high in sugar and HFCS. That's why you can eat a few ounces of steak and a plate of cookies. * Fat decreases ghrelin production for much longer than carbohydrates do (three hours to one hour), leaving you less hungry. Peptide YY and Fiber PYY is another satiety hormone produced in your small intestine. The trigger occurs about 20 feet down your small intestines. It tells your brain that you are "done" eating. You have to work *really* hard to eat once PYY has signaled satiation. * Combined soluble and non-soluble fiber speed the passing of food through your small intestine, causing PYY to be released earlier. * While not directly related to carbohydrates, most high carb foods have the fiber removed to increase shelf-live. This slows the release of PYY, allowing you to eat more. * Fiber has been shown to increase good gut bacteria, which also reduces the number of calories absorbed from food and has positive benefits for many chronic diseases. * Fiber also reduces the flux of sugar, and therefore insulin, during digestion. This is why whole fruit is OK, even though it contains much fructose: the fiber slows the absorption to a level the liver can cope. AMPK AMPK is a key signaling enzyme in the body's energy manipulation process. It is key to driving homeostasis. * AMPK is significantly increased on a low-carb diet. * Increased AMPK increases glucose uptake, glycolysis, fatty acid oxidation, mitochondrial iogenesis, all of which are good. * In addition, increased AMPK inhibits gluconeogenesis, glycogen synthesis, fatty acid and cholesterol synthesis, and insulin secretion, all of which we don't want to have happen. * If you've heard of the positive effects of starvation diets on the lifespan of mice (which don't hold true for humans, though low carb might), this may be the metabolic pathway that accomplishes that. Cortisol Cortisol is the "flight or fight" hormone. It is excreted by the adrenal glands. * When combined with insulin, cortisol causes fat to be stored viscerally (abdominally), which is the place that causes metabolic problems. * Chronic stress leads to chronically high levels of cortisol. Again, combined with insulin, this increases metabolic syndrome. It also causes the brain to signal "eat" in an attempt to ensure there is enough energy around to fight the stress. * Reducing insulin doesn't directly reduce cortisol, but it does help limit the damage of high chronic cortisol levels. =Diseases= The carbohydrate, sugar-and-gluton rich diet is the cause of or is strongly implicated in many diseases. Non-Alcoholic Fatty Liver Disease This disease is exactly the same as Alcoholic Fatty Liver Disease and is caused by the consumption of fructose in large quantities. The liver is the organ that processes fructose, and, if quantities are too great, it stores that fructose inside the liver. As more fat gets stored, liver function decreases and insulin regulation suffers. Diabetes High blood sugars create an environment of glucotoxicity. In this environment, damage is done to the Beta cells (the insulin producers) in the pancreas.The beta-cell in human type 2 diabetes This occurs in an environment as low as 100 mg/dl, a level which is considered normal and can be passed simply by eating a sandwich. The pancreas is hit again by the high triglycerides and VLDL fatty acids that come as a result of ingesting carb rich foods. Strike number two against the beta cells. Finally, the visceral fat that is the hallmark of a high-carb diet is highly inflammatory. This inflammation, such as oxidative injury, leptin, interleukins, and tumor necrosis factor, provide a third strike against the beta cells.The beta-cell in human type 2 diabetes Over time, these factors cause the death of beta cells, cells which can't be replaced. Eventually, the number of beta cells can be reduced to less than 50% of their original number.Beta-cell failure in diabetes and preservation by clinical treatment Cancer There is some evidence that glucose/insulin spikes may flip the switch that causes benign tumors to become malignant. There is also evidence that many kinds of cancer are unable to grow in (and may, in fact, be harmed by) an environment containing the byproducts of a ketogenic diet.Targeting insulin inhibition as a metabolic therapy in advanced cancer: a pilot safety and feasibility dietary trial in 10 patients.()Is the restricted ketogenic diet a viable alternative to the standard of care for managing malignant brain cancer?Metabolic management of glioblastoma multiforme using standard therapy together with a restricted ketogenic diet: Case ReportThe ketogenic diet reverses gene expression patterns and reduces reactive oxygen species levels when used as an adjuvant therapy for glioma Not all cancers would be suject to this, but it appears that many types of the "Western" cancers (e.g. lung, colon and breast cancers) might be positively impacted by a ketogenic diet. Metabolic Disorder Metabolic disorder, which includes overweight, Type 2 diabetes, high blood pressure, high cholesterol, gout, and other problems, occurs when the body's macro energy system goes out of kilter. While not, strictly speaking, caused by carbohydrates, it is caused by a viscious circle that includes consumption of food that is easily converted into glucose, the blood sugar swings that causes, and, finally, the cravings those swings cause that result in the consumption of more easily-converted food. Alzheimers Several studies have demonstrated that the "neurofibrillary tangles" of proteins found in the brains of Alzheimers patients are in part caused by a lack of insulin sensitivity in the brain, and just as in Type 2 Diabetic patients, the disease begins as a sort of insulin resistance.The ketogenic diet as a treatment paradigm for diverse neurological disordersKetone bodies as a therapeutic for Alzheimer's disease. Parkinsons =Important Things to Know= * Cholesterol as tested is only a so-so indicator of potential heart disease. A much better predictor is APO-B, the particle that will cause blood plaques. Low-carb diets have shown good results in decreasing APO-B particles. * In the meantime, using the ratio of triglycerides to HDL is a better indicator than any other commonly tested cholesterol number as to your metabolic health, as it is a good indicator of oxidized LDL, insulin resistance and metabolic syndrome. * Speaking of cholesterol, LDL has been called the "bad" cholesterol, but that is an oversimplification. There are two types of LDL cholesterol: heavy, dense LDL and light, fluffy LDL. Light, fluffy LDL is good for your body, but, unfortunately, is not distinguished in normal testing. Low carb diets may increase LDL numbers, but they do so by increasing the light, fluffy, "good" LDL. * Omega-3 fatty acids increase insulin sensitivity in cells, allowing your body to produce and use less insulin. Low-carb diets tend to be higher in Omega-3 fatty acids. * Obesity is a pretty good marker of ill health, but normal weight isn't a good marker of good health. 20% of overweight people are metabolically healthy; 40% of normal weight have metabolic syndrome. Focusing on weight is the wrong thing. * Corn is subsidized by the government to the tune of billions of dollars per year. This keeps prices lower than the market would otherwise bear. This allows food manufacturers to put HFCS into places that sugar would never go. * Of the 600,000 food items sold in the US, 90% are laced with sugars. * Ten companies provide 90% of the food sold in the US, and, collectively, they spend $1.6 billion or more marketing to children (we didn't like tobacco companies doing that); spend nearly $1 billion researching the right combination of salt, sugar and fat to give food the right combination of shelf life, "mouth feel", and craving; and fund initiatives through the "Center for Consumer Freedom" to lobby against anti-obesity initiatives. * The World Health Organization proposed limiting sugar to 10% of calories due to sugar's impact on chronic disease. Due to lobbying by the World Sugar Research Organization, the Bush administration threatened to cut off funding for the WHO if they published the report and, as a result, got the report deep-sixed. This is but one of many instances of the government siding with the deep-pocketed agricultural lobby at the expense of our nation's health. * The US Dept of Agriculture defines what we should eat. Their charter is to promote the sale of agricultural products. There is a deep conflict of interest here if "what should we eat" causes the sale of fewer agricultural products. =Unhealthy Foods= Many very-high carb foods have problems. The problems have been exasperated over the last 50 years as our grains have been altered genetically to produce higher yields at lower costs. Wheat is the worst offender in this category. * Grains are high in phytic acid which binds essential minerals in the intestine and prevents them from being absorbed. * Gluten can damage the intestinal lining, cause pain, bloating, stool inconsistency and tirednes. Gluten consumption has also been associated with schizophrenia and cerebellar ataxia, both serious disorders of the brain. =Final Thoughts= I realize this has been long, so I'll be quick here. The US is spending $150 billion on health care due to obesity. It is also losing $75 billion in lost productivity. The obesity pandemic is a serious crisis. Thirty years ago, the low-fat, high-carb diet was thrust upon us, even though the good science of the time didn't support it (unfortunately, it also didn't contradict it as fully as was needed to stop the personalities pushing low-fat). In the intervening years, we've seen an explosion in the number of obese people, an explosion that has followed the industrial diet into every country it has touched. We've also learned much more about how the body utilizes various macro-nutrients. All of that knowledge we've gained has been explicitly clear: a calorie is not just a calorie and sugar does nothing good and quite a bit bad to your body. There is no question the science is not complete. There will be adjustments as we continue to learn. That's the nature of science. But these results come from 100 years of consistent experimental results. This isn't a change in what science was showing 25 years ago, but rather an interpretation of the data outside of financial and personality interests. Due to those conflicting interests and heavy lobbying they supply, it will be a long time before the government changes its stance. But my stance has certainly changed, and I will be teaching this to my kids. =Worthwhile Books to Read= * Why We Get Fat by Gary Taubes * Fat Chance: Beating the Odds Against Sugar by Robert Lustig * Good Calories, Bad Calories by Gary Taubes * Salt Sugar Fat: How the Food Giants Hooked Us by Michael Moss * The Paleo Solution: The Original Human Diet by Robb Wolf and Loren Cordain * Minding My Mitochondria: How I overcame secondary progressive multiple sclerosis (MS) and got out of my wheelchair by Terry L. Wahls =References=